Electrical burglar-alarm.



I B. F. SHARP.

ELECTRICAL BURGLAR ALARM.

APPLIGATIOH FILED nu 21, 1912.

' Patented Apr. 15, 1913.

WITNESSES To all whom it may concern;

BENJAMIN I. SHARP, OF AMIBDEB, PENNSYLVANIA. v

annex-B1041. Rosana-ALARM.

Specification of Letters Patent.

Application filed m 21, 1912. seriaim. cease-1.

Be it known that I, BENJAMIN F. SHARP, a citizen of the United States, residing at .Ambler, in the county of Montgomery and State of Pennsylvania, have invented certain new and useful Improvements in Electrical Burglar-Alarms,

of which the following isa specification. T

The ob ect of my invention to provide an electrical burglar alarm of novel,'simple and efiicient construction, employing an electric circuit including an alarm element and two openingfand'closing devices, and employing a plurality of additional electric circuits provided with means to open and close said devices,"whereby the .closing of one of said devices by a burglar entering a building will actuate the "alarm element, whereby the opening of the device closed by the burglar will stop the actuation of the alarm, element, and whereby the closing and I opening of the other'of said devices will set the entire alarm system into and-out of operative position, all as willbe hereinafter fully described and particularly claimed.

The accompanying drawing illustrates my improved sys'tem diagrammatically.

Referring to the drawing, 2 d esignates a frame or casing ofinsulating material in which are mounted four electromagnets 3,

I 4, 5 and 6. This'frame, 2 may be of any suitableshape for its intended purpose.

a The electromagnets are included in four to the upper portion-of the door 13. is a electric circuits supplied with current from a common source or battery 7 Included in the circuits with the four electromagnets 3, 4, 5 and 6 are four normally open contact making and'breaking'devices 8, 9,- 10 and 11, respectively. 1

The devices .9, 10 and Hate common, well known, normally open push buttons. The device 8 is adaptedto restnormally open and to be closed by the openin of a' door or window of the uilding to connection with a door,. 12 designating a part of the frame, in section, in-which thedoor 13 is mounted, the door 13 bein movable into and from the frame 12. ured bracket 14 having a rojectin upper end adapted. to engage an move t e lower end rotected by'the alarm.- The device 8 is s own in" v, Patented A r. 15, he;

of. an arm 15 whenfthedoor is yeseai'rteii arm 15'is,p1voted,-at 16,- to a bracket 1'7] secured to the frame 12. {The upper end of the arm 1!) is adjacent and normally'out of contact-witha contact spring 18 secured to the frame 12. The bracket 14, arm 15.

and spring 18 are; so related embarks:

that when the door 13. is. opened or moved Y in the direction of the; arrow, the bracket '14-will engage-and move the arm 15 'andcause the upper end 'thereo'fto make 'conj-a tact with .the.sprin'g18.- The arm 15 per mits the door 13 'tobe readily-opened and" closed at all times, thebr acket 14 moving the arm 15 until the bracket jescapesthe arm,

and, the arm assuming the position shown by gravity.-, V w

The circuits for the devices 8, 9, 10 andll and electromagnets 3, 4, 5 and 6, res ectively, may. be ,tracedas follows: Lea ing from the bracketl'l' and arm 15' to the electromagnet 3 is a-wire 19; leading from; the

electromagnet 3 is a wire which 'iscon-' 'nected to a battery wire 21 extending from one side of the battery 7 leading from the other side of the battery 7 is a battery wire 22 which is connected to "a'wire '23 leading to the contact spring 18 thus completing the circuitfor the ,elwtroma gnet a; Leading" from the push button 9 to the electromag-w net 4 is a wire 24, leading from theelectromagnet 4 to the battery "wire 21 is a wire 25' and leading from the battery 'wire 22' to the push button 9' is a wire 26, thus com,

pleting the circuit for the electromagn'et 4.

Leading from the push button .10 to' the a electromagnet 5 is a wire 27, leading from the electromagnet 5 to the battery wire 21- wire 22to the push button 10 is a wire 29, thus com;leting thecircuit for the electromagnet' Leading from the push button;

.is' a wire 28 and leading fromjthe battery 11 to the electromagnet ti is a wire 30 leading from the electromagnet 6 to thebattery' wire 21-is a wire 31 and leadin from the" battery wire 22 to thevpush but a 11 is a.

wire 32, thus completing the circuit for the electromagnet 6.

The electro'magnets 3, 4,5 and 6 are pro vided with spring armatures"33, 34 35'and 36, respectively, which are secured to and reject from parts-of the casing 2, as shown. lhe armatures 33 and 35 normally in the full line positions shown, and these armatures may be sprung back to the dottedline positions shown under the influence of the electromagnets 3 and 5. The armatures 34 and 36 rest normally in the dotted line positions shown, and these armatures may be sprung back to the full line positions shown under the influence of the electromagnets 4 and 6.

The armatures 33 and are provided with projecting arms 37 and 38, respectively,

' as shown. When the armature 33 is in the 1 makes'electrical contact with a contact plate 39 secured to the casing 2 for a purpose hereinafter explained.

The armatures 35 and 36 are provided with projecting arms 40 and 41, respectively, as shown. When the armature 35 is in the normal or full line pos1tion, its arm 40 engages the arm 41 of the armature 36 and holds it in the full line position away from its normal. or dotted line position and when the armature 36 is in its normal or dotted line position, its arm 41 engages the arm 40 of the armature 35 and holds it in the dotted line position away from its normal or full line position. When the armatures 35 and 36 are in the full line, osition, 'electrical contact is made between t e-arms 40 and 41, electrically connecting the armatures 3 5 and 36; and when the armatures 35 and 36 are in the dotted line position, the arm' 40' rests upon an insulating pad 48 on the .arm

41, and the electrical connection between the armatures 35 and 36. is broken fora purpose hereinafter ex lained. v

The alarm evice, an ordinary electric bell 42 is included in an electric circuit sup lied with current from a battery 43; an inchided in this circuit are the armatures 34, 35 and 36 and the contact late 39. The bell V circuit may be traced as ollows: from battery '43, wire 44, contact plate 39 armature 34, wire 45, armature 35, armature 36, wire and 6 are open at the closing against being entered without .-e o' 46, bell 42 and wire 47 to battery 43.

The operationis as follows: The parts are in the'position shown in the drawings when set to protect a building for the night actuating the alarm bell 42. In this position of the' parts the circuits for the 'electromagnets 3, 4, 5 devices 8, 9, .10 and 11, res ectively, the circuit for the bell 42 is closed etween the armatures'35 and 36.'

Now, should the door l3 be opened by a person attempting to enter the building, the arm 15 will be moved into contact with the spring 18, closing the circuit for the electromagnet 3 and causing it to attract the armature 33 to the dotted line position. This operation raises the arm 37 from the end of the arm 38 and permits the armature 34 to move to its normal, dotted line position and into, contact with the plate 39, thereby closing the circuit for the ell 42 "and actuating the same. The arm 37 rests upon the arm 38 and the armature 34 rests against the plate 39 after the circuit of the electromagnet 3 is broken, I and the bell 42 continues to ring until the push button 9 is operated to close the circuit for the electromagnet 4 causing it to attract the armature 34 to the full line position away from the plate 39, breaking the circuit for the bell 42 and freeing the armature 33 which returns to the full line position and holds the armature 34 out of contact with the plate 39.

When it is desired to set the parts in position so that the opening of the door 13 shall not actuate the bell 42, during the daytime for example, the push button 10 is depressed,

thereby closing the circuit for the electromagnet 5,caus1ng it to attract the armature 35 to the dotted line position and move the arm 40, up from engagement. with the arm 41 and'open the bell circuit. The raising of the arm 40 frees the armature 36 and permits it to move to the dotted line position and move the insulating pad 48 beneath the arm 40, 'so that when the button 1.0 is released, the pad 48 will maintain the armatu're 35 raised and the arm 40 out of contact with the arm 41.

When the armatures 35 and 36 are in. the dotted line position, and it is desired to set the parts in the position shown, so that the opening of the door will actuate the bell 42, the push button 11 is depressed, thereby closing the circuit for the electromagnet 6, causing it to attract the armature 36 and move the pad 48 and arm 41 from beneath the arm 40 and permit the armature 35 to resume its normal or full line position; whereupon, after the button 11 is released, the arm 41 will engage the arm 40 and close the bell circuit between the armatures 35 and 36, and the parts will be again in the position shown.

I claim. The combination of a normally open first electric circuit includin an electromagnet, a normally open secon electric circuit including an electromagnet, a normally open third electric circuit including an electromagnet, a normally open fourth electric circuit including an electromagnet, means 0perative to close the first circuit, means op erative to close the second circuit, means operative to close the third circuit, means operative to close the fourth circuit, and a fifth electric circuit including a translating cuit and opened bythe electromagnet-of the element and having two opening and closing fourth circuit. devices, one of said devices being closed by In testimony whereof I afiix my-signature the action of the electromagnet of the first in presence of two Witnesses.

circuit and opened by the action of the elec- BENJAMIN F. SHARP. tromagnet of the second circuit, v and the Witnesses: other of said devices 'being closed by the ac- WM. HARRISON SMrrn,

tion of the electromagnet of the third cir- A. V. GROUPE. 

